Abstract
Adenoid tissue was obtained at operation from 27 children admitted for adenoidectomy and from 6 controls. The occurrence of cells with cytoplasmic immunoglobulin was studied semiquantitatively by immunofluorescence microscopy of tissue sections, by which localization, number of cells and class of immunoglobulin were determined. No differences were found between patients and controls. Cells isolated from adenoid tissue were compared with mononuclear leukocytes obtained from the blood. More B lymphocytes were found in the tissue, in particular IgM-carrying cells. This was more pronounced in the patient group. Cells were stimulated in culture with polyclonal activators and microbial antigens. The response of adenoid lymphocytes to Haemophilus influenzae (HI) was high in 7/27 patients; all patients in whom throat culture was positive for HI were low re-sponders.